Phospholipid Role (Phosphatidylserine)

an example of nature using two chemicals it likes in non-primary roles (meaning serine and lipids are being used but not in ways that we would call primary like we would the buiding of proteins and membranes, respectively)

Tyrosine

Phosphorylation

Again, a control mechanism

Planar

Can lay against another planar molecule to protect the Pi electrons (e-)

Asparagine and Glutamine

When we sequence we hydrolyse stuff and this process makes these two amino acids look the exact same

Asparagine has a special role as it is the only amino acid sugars can be attached to so as to make glycoproteins.

Cysteine

An oxidation reduction reaction makes disulfide bonds between two Cysteines spacially (as opposed to sequentially) near to one another in a protein

These disulfide bonds give a tight, precise conformation to the protein. They hold the tertiary structure together.

Disulfide bonding is reversible.

Disulfide bonds are not made by hydrolysis!

Two cysteine disulfide bonded are called a cystine.

Glycine

Can be a neurotransmitter like acetylcholine (this is done as a monomer, not in a protein or polypeptide form)

Glycines are found in tight folding areas of proteins because they do not have an R-group to get in the way.

Glycines are found in porphyrins, purines and pyrimidines (the latter two from nucleic acids)